environment, youwill find this layer of chert. it's in all colors, purple, green, red, blue. it's a beautiful rock. . >> one thing i wanted to ask you, the review in the paper recently on sunday said that your book is different from all the other books about the anastazi because you brought out some of the non-flattering parts of their culture like violence. how did you conclude that they were a violent culture? . >> well, i didn't necessarily conclude they were a violent culture, i just concluded there was violence in their culture. the evidence is very clear where you find masker sites, where every place you drop a trench there are bodies, unburied bodies missing their heads, in some cases where there will be a head in one room and you can match it up to the body which is in another room 100 yards away and they didn't just end up there; somebody took the head off. and there will be places where it's all femurs, all gathered together. and places where it's obviously some kind of warfare event where people are all huddled into one spot and they have all been burned there. the record is very c